The NIMH Screening Program was established in order to evaluate natural or synthetic compounds with potential central nervous system (CNS) activity from individual scientists engaged in basic or preclinical research. Centrally active natural product extracts are especially of interest in order to search for novel pharmacologic mechanisms. Screening costs are paid for by the NIMH; there are no charges to investigators. Under this contract, investigators may submit compounds for evaluation in receptor- based assays which may be predictive of psychotherapeutic activity. The main purpose of this contract is to aid in the design of new therapeutic agents, to better predict and understand mechanisms of potential side-effects, and to better understand the mechanisms of therapeutic action of new agents. In order to accomplish these broad aims, the NIMH strongly encourages investigators to follow up compounds which display activity (i.e., inhibition of ligand binding or enzyme activity) with additional testing. Additional tests may include, for example, receptor subtypes, preliminary IC50, functional assays, or in vivo activity and will be determined on a case-by-case basis. The NIMH expects that investigators submitting compounds will: 1) publish results obtained from the screening analyses (publications should acknowledge the service provided by the NIMH program); and, 2) provide the NIMH with a copy of the published manuscript. It is planned that the data generated from this program will be entered into an NIMH structure-activity database. This information will serve as a resource to assist in the design and discovery of novel compounds with potential use in the treatment of mental health disorders.